Process and apparatus for cracking oil



June 24, 1930. EGLOFF PROCESS AND APPARATUS FOR CRACKING OIL OriginalFiled Dec. 6. 1920 Patented June 24, 1930 UNITED; STATES PATENT oF lcaeus'rav Esters, orcnIcAeo, ILLINOIS, ASSIGNOR 'ro UNIVERSAL OILrnonuc'rs COMPANY, or CHICAGO, ILLINOIS, A CORPORATION or sou'rn naxo'rarnocnss Ann APPARA'I US FOR CRACKING OIL Application'filed'neeniber 6,1920, Serial No. 428,787. Renewed Mai; 25, 1929'.

This invention relates to improvements in a process and apparatus forcracking oil, and

refers more particularly to the conversion of such petroleumconstituents as fuel oil and heavyasphaltic crudes'intolighterhydrocarbons, such as'gasolene, kerosene, gas oil and the like, althoughin its broadest aspects the invention relates to the conversion of heavyto lighter hydrocarbons. In the cracking of petroleum oil, certain ofthe generated vapors are iiisufliciently converted, and it is desirabletofreturn them to the system for further treat- Inent. The heaviervapors so returned are known as reflux condensate forthe reason thatthey are the result of reflux condensation in one form or another. Thisreflux condensate is of a different character than the 'raw oil fromwhich it originally came, and

in many types of oils, should be, if possible,

subjected to diflerent conditions of cracking,

particularly as to temperature and pressure, than should the raw oilitself." At the same time, it is desirable to treat the oil in aneconomical and simple apparatus, as the cost of construction andmaintenance of apparatus for cracking oilis an item of such moment as tofrequently make the process, however desirablein itself, commerciallynot feasible.

. The present invention overcomesthis objecvided with the oil or gasburners and 6,,and the furnace is provided with a stack 7. In the" lowerchamber is mounted the raw oil heating coil 8, which may take the formof several hundred feet of four-inch pipe,"the inlet side ofwhichis-connected by feed line 9 to raw oil pump 10, provided withthrottle valve 11. This raw oil pump is connected to any suitable sourceof raw oil sup-;

ply. The upper end ofthe coil 8 isprovided. .tengperature and, pressureto which the raw &

with a discharge line 12, in turn connected .to the main transfer line13, leading to the expansion chamber'14 located outside of the firezone. -A throttle valve is inter osed in the line 13. In the transferline 12 1s interposed a pump 16, provided on either side with valves 17and 18. The 'pump may be bypassed through bypass line 19, havingthrottle valve 20. The arrangement is such that the oil may be deliveredfrom the coil 8 to the I expansion chamber either at the same pressureas in the 001]. or at a reduced pressure or at an Increased pressurerelative to the 0011.

The lower end of the expansion chamber is provided with a residue drawoff line 21,

having throttle valve 22. It is also provided fles 26. The upper end ofthe dephlegmator is provided with vapor outlet pipe 27, having throttlevalve 28, and leading to the .con; denser coil 29, seated in condenserbox 30.

Thelower end of the coil 29' is connected by pipe .31, having throttlevalve 32, to the upper end of the receiver 33. This receiver 33 has aliquid draw ofl pipe- 34, controlled by throttle valve 35, gas outletpipe 36, controlled by throttle valve 37. It is also p'rovided withliquid level gauge 38.

The reflux condensate is drawn off fr omthe bottom of the dephlegmatorthrough reflux line 39, having throttle valve 40, and leading to theinlet side of feed pump '41.

The discharge-side of the pump 40 is connected by means of feed line 42,having throttle valve 43; to the lower end of a heating coil 44,,seatedin the combustion chamber 3. This coil 44 may be of the same length andsize as thecoilS, or it may be of in-- creased diameter or increasedlength of pipe, particularly if there is more reflux condensate to betreated than raw material. In the cracking of certain petroleums thiswill be the case, the amuont of reflux, of course, depending also uponthe temperature and size of the dephlegmator, the desired end pointproduct to be obtained, as well as uponthe sion chamber.

oil is subjected. In other words, all factors must be taken intoconsideration in regulating the size of the coils relative to eachother. From extended practical experience in the 5 cracking of petroleumoil, it is impossible to definitely give figures for all oils, butanyone skilled in the art will have no difliculty in regulating thesefeatures.

The other end of the coil 44 is connected by pipe 45 to the maintransfer line 13. A pump 46, having at either side valves 47 and 48, isinterposed in the line 45. The pump may be bypassed by meanS of thebypass pipe 49, in which is interposed throttle valve 50. Thearrangement is such that the reheated reflux condensate may be deliveredfrom the coil 44 tothe expansion chamber under the same, increased ordecreased pressure relative to the pressure in the heating 20 coil. 4

Suitable pressure gauges 51 are provided 1 in various parts of thesystem as shown.

In carrying out the'process, raw oil, as for example Kansas or Oklahomagas oil of 31 35 degrees Baum gravity, may be continuously fed throughthe first heating coil, and there subjected toa temperature of say 750de- "grees F., care being taken to deliver it in substantially liquidcondition to the expan- The reflux condensate may be heated to atemperature varying between 600 and 8OQ degrees F. A uniform pressure,if desired, may be maintained on the entire system clear through tothereceiver, as for 35 example, pounds. A process may be carried outwith'this apparatus in which the? pressure on the raw oil coil may besay pounds, 200 pounds on the reflux condensate coil, and 100 pounds onthe expansion chamber, dephlegmato'r and condenser. One pro-. nouncedadvantage of the present invention is the ability to subject the refluxcondensate in the same apparatus and in the same .furnace toindependently regulated conditions oftemperature and pressurerelative'to that .to which the raw oil is first subjected.

I claim as my invention: 1. A process for converting oil, comprisingpassing a stream of charging oil through a ture sufficient to vaporize asubstantial part thereof, in introducing the heated hydrocarbons under apressure, in excess of that maintained on the charging oil duringpassage through the heating zone, to an enlarged expansion chamber wherevaporization occurs, in subjecting the vapors to dephlegmation, inheating the reflux condensate in a separate stream to a crackingtemperture, in passing the heated reflux condensate under pressure tosaid'expansion chamber, and in Withdrawing the unvaporized residual oilfrom the expansion chamber.

2. A process for converting oil, comprising passing a stream of chargingoil through heating zone to be subjected to a tempera-- I a heating zoneto be subjected to a temperastream to a cracking temperature whilemaintamed under a pressure 1n excess of the pressure on the charging oilpassing through the heating zone, in passing the heated refluxcondensate to said expansion chamber, in withdrawing the unvaporizedresidual oil from the expansionchamber, and in maintaining asuperatmospheric pressure on the oil' undergoing conversion.

3. A process for cracking hydrocarbon oil, comprising the simultaneousand independent subjection of a relatively low boiling point hydrocarbonoil and a relatively high boiling point hydrocarbon oil to higher andlower cracking conditions of temperature and pressure respectively,thereafter commingling the heated oils in a common zone maintained undera pressure higher than the pressure to which said relatively highboiling point hydrocarbon oil was previously subjected.

4. A continuous process for cracking hydrocarbonf oils, comprisingsimultaneously advancing in independent streams a relativee ly high,boil ing point hydrocarbon oil and a relatively low boiling pointhydrocarbon oil through a heating zone, subjecting the stream ofrelatively low boiling point hydrocarbon 011 to higher conditionsoftemperature and pressure than maintained on the stream of relativelyhigh boiling point bydrocarbonoil, delivering the heated oil from saidindependent streams to an enlarged zone,'mai-ntaining a pressure in saidenlarged zone in excess of the pressure maintained on said stream ofrelatively high boiling point hydrocarbon oil, and subgeicting vaporsevolved from the oil to dep egmation and condensation.

5. A process of. oil conversion, comprismg maintaining. a body of heatedhydrocarbons in an enlarged zone, where substantial vaporization--occurs, subjecting vapors togefiux condensation, tov condense theheavier vapors, passing the reflux condensate resulting from thecondensation of the heavier vapors in an advancing stream through aheatingzone, where it is subjected to cracking conditions of temperatureand pressure, delivering the heated condensate to said enlarged zone,simultaneously heating an ndependent stream of charging oil, fordelivery to said enlarged zone, to a temperature sufiicient to cause asubstantial vaporization thereof in said enlarged zone, introducing saidheated charging oil to the enlarged zone,

under a pressure in excess of the pressure maintained on saidindependent stream of charging oil during the heat treatment there- 6.An apparatus for cracking hydrocarbon oil, comprising a plurality ofheating coils, an enlarged expansion chamber, means connecting each ofsaid coils to said enlarged expansion chamber, means for supplying oilto each of said coils, means for maintaining independently controlledpressures on the oil in each of said coils, means, associated with themeans connecting -each coil to said expansion chamber, for introducingoil from the associated coil to the expansion chamber, at a pressure inexcess of the pressure maintained on the oil in such associated coil.

7. A process for cracking hydrocarbon oil, comprising the simultaneousand independent subjection of a relatively low boiling point hydrocarbonoil and a relatively high boiling point hydrocarbon oil to higher andlower cracking conditions of temperature and pressure respectively,thereafter commingling the heated oils in a common zone maintained undera pressure higher than the pressure to which said relatively low boilingpoint hydrocarbon oil was previously subjected.

GUSTAV EGLOFF.

